Steam-engine.



R. O. STEVENS. STEAM ENGINE. APPLICATION HLED SEPT. 26, ma.

'Patented oen. s, 1914.

ROBERT C. STEVENS, OF ERE, PENNSYLVANA, ASSGNOR TO SKNNER ENGINE COLI- PANY, OF ERIE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

STEAM-ENGINE.

Specification of Letters Patent.

Application filed September 2G, 1915,

atentedl @ein MMA. Serial No. 791,995.

lle it known that l, loninvr C. tl'rnvnxs, a citizen ot' the llnited States. residing at vlh'ie, in the county ot' Erie and State oi" Pennsylvania, have invented certain neu' and useful Improvements in tateainsllngine 5 and l do hereby declare the followingl to be a full, clear, and exact description ot the invention, such as will enable others skilled in the art to Whiehfit appertains to make and use the same, reference bein;r had to the accompanying drawings, and to the letters of reference marked thereon, 'forming part of this specification.

My invention relates to steam engines olE that type wherein the steam enters the cylinder at the ends thereotI and exhausts therefrom at points intermediate ot the ends ny means of independent exhaust ports, known to the art as indepei'ident exhaust unitlou engines. t

Heretotore in the emistruetion oi' steam engines having independent exhaust ports, it llas been necessary to provide a plu "v otl valves to open and close said ports 'to the admission and exhaust of steam, which en tails a multiplicity ot ports in the valve fear and consequent eoinpli' tion lt is therefore an oi dect of in v invention to adapt a steam engine haring,Y independent exhaust ports to the use ol a single valve hy means of which all of the ports of the engine may be properly opened and closed with relation to the en :rinc piston.

'lhe lieatuies of my invention are hereinafter shown and described and are illustrated in the accompanyingy drawings, in n'hieh A Figure l, is a longitudinal central section ot' an engine cylinder and valve, embodyingl my invention. Figi'. 2, is an end view in eleration, et the same.

ln this drawing A, indicates an engine` ovlinder. A and Ai, indicate the cylinder heads; l. indicates the valve-chest, B2, indicates the exhaust pipe B5, indicates the steam inlet pipe; C, indicates the piston, and C, indicates-the piston-rod; l), indicates thel eneine valve, and D', indicates the valve-stem.

'lhe cylinder A, is provided with steam ports a and a', and with exhaust posts a2, and a. 'lhe steam ports a and a', and the exhaust ports o2 and as, lead toward the intermediate portion of the valve chest B, and have their exit through the Valve-seat surtace I), ot the inner wall thereof. Upon the valve-seat surface l place. a valve'l, which is d 'nned to receive the exhaust steam in its interior and `duide it to the exhaust pipe l?, and which is so proportioned on its inner or exhaust edges, d and al', that these edges never uncover the entrances of the steam ports f1- and ai', and the outer or steam edges (Z2 and d, will alternate@T cover and uncover the entrances into the, steam ports ,fr and u', so that the steam exhaust will be regulated by they valve l), uncovering the eX- haust ports and o and the compression is regulatedL by the edges ot the piston C, passing over and clos-ine' the exhaust ports a2, and uf", or under certain conditions said c0mpression' may be determined by the exhaust edejes (Z and closing one or other of the exhaust ports u or a, beiore they are completely covered by the piston .Q The exhaust steam passes thro k 1 the valve D, and l therefore have shown said valve as being iwel'erably oi" the st anidialanecd expanding 5 pe. as it is necessary to perfectly separate he steam vvhich is introduced into the valve liest lil. around the valve D, for operating ie entrino, 'from the exhaust steam within ie valve. but it ivill be obvious that other l 'tl tl iii parting' from my invention.

tf1-om the drawing;v and the foregoing*J deseription` it will be obvious that I am en abled to construct an engine having' ashort' c \jlinder. and short, light; piston similar to the ordinary steam engine, but with the added ai'lvantae'es ot' independent exhaust ports through which the cool steam may escape without coolingr the Walls of the steam intake ports, without addition of a multiplieity of valves and their accompanying' eonmlieations of valve gear for opening and closing` said exhaust ports.

ln operation` when steam is admitted to the valve-chest B, around the valve D, therein, and the valve is in the position shown in the ilrawing, the piston C, will be thereby moved toward the right` and the exhaust from the cylinder Will loe through the eX- lraust ports a3, which Will remain uncovered by the valve D, until about when said ports are covered by the piston C, and compression commences and continues to the end ot that stroke of the piston, the valve D, during' this time maintaining the exhaust ports o2, closed so as to confine the steam rms ol' valves may be lutilized Without de- 35 a cylinder having, steam inlet ports and ins within the cylinder' to near the end oft the pieton stroke. rlihe valve D, iS moved to ward the lett, which causes the steam port CL, to be covered, thereby cutting oliQ the steam thereirom, and also causerl the exhaust port e, to lie covered, and the exhaust port a, lo lie opened, to exhaust and the steam port if., twlie opened Vto steam. which operation o'lt the valve il, and piston C, continues until atezun is excluded from the valve-chest B.

From the 'foregoing description of the construction and operation of an engine enil odying my invention, it will lie obvious that hy means of my invention l :un enabled to ctaubine the advantages oi `the simple slide valve engine Awith those of the independent exhauet unitlow engines without coinplieation of parts, incident to multiple valveS.

Therefore having full y shown and de.- seribed my invention so to enalile others to utilize the same, what' l claim as new and desire to secure by Letterepatent, is:u

l. The combination in a steam engine, of a cylinder having a steam intake port in the wall ot said cylinder at the end thereof, an independent eXhauSt port in the Wall of said cylinder spaced from said intake port, a piston in said cylinder, valve' chest with which said poi-t communicates, a valve therein vadapted to alternately open Said Steam port to steam, and Said exhaust port to exhaust in proper time with relation to the movement oi the pieton.

2. The Combination in a steam engine, ot

dependent exhaust ports in the Wall thereof spaced from said inlet porte, a, piston in said cylinder, heads on said cylinder, a valve-chest with which said ports communicate, a hollenv valve therein adapted to 40 alternately open said exhaust ports and receive the exhaust steam thereinto and conduct it to the engine exhaust pipe, and t0 alternately open said steam inlet ports to admit ste-ain thereinto 1i-om said valve-chest, 45

in propei.` time with felation to the nievement of said piston, .sulietantially as Set ifortlr 3. ln a steam engine, the combination of a cylinder having' steam inlet ports at its 50 ends, and indel'iendent exhauet ports in the Walls thereof spaced Yt'roln said inlet ports located between each oi" said steam inletl ports and the middle of said cylinder, a piS- ton in said cylinder adapted to pass each 55 of said exhaust ports during' its movement toward each end ot the cylinder, heads on said cylinder, a valve cheet with which all of Said ports communi fate, and a valve therein adaptedl to alternately open said steain ports 60 to steam and said exhaust ports to exhaust, in proper time with relation to the movement of said pieton, sulietantially as set forth.

in tmtimony whereof I atlix my Signature, G5

.in presence of two witnesses.

' ROBERT l. STEVENS.

lllitnesees i-I, M. S'rononon,

P. V; Girronn. 

